1. Field of the Invention
The present invention relates to an image forming apparatus and an image forming method for forming an image on a recording medium.
2. Description of the Related Art
Japanese Patent Application Laid-open No. 11-348256 describes an ink-jet recording apparatus comprising a reaction liquid printing head and an ink composition printing head which are movable in the main scanning direction and a recording medium transport mechanism which transports a recording medium in the subsidiary scanning direction perpendicular to the scanning direction. In the ink-jet recording apparatus, a reaction liquid is discharged onto the recording medium from the reaction liquid printing head, and an ink composition is discharged onto the reaction liquid from the ink composition printing head. In this way, the ink composition and the reaction liquid are reacted with each other on the recording medium, and it is possible to form an image in which the color density is high and the blurring and the printing unevenness are suppressed.
However, in the ink jet recording apparatus described in Japanese Patent Application Laid-open No. 11-348256, a mist of the reaction liquid and a mist of the ink float in the apparatus when the reaction liquid is discharged from the reaction liquid printing head and when the ink composition is discharged from the ink composition printing head. As for the mists as described above, if the reaction liquid mist is adhered to the discharge surface of the ink composition printing head (portion at which discharge ports for discharging the ink composition are formed), and the reaction liquid mist is mixed with the ink composition existing in the vicinity of the discharge surface and the discharge ports, then a coloring agent of the ink composition is coagulated or deposited. On the other hand, if the ink mist is adhered to the discharge surface of the reaction liquid printing head, and the ink mist is mixed with the reaction liquid existing in the vicinity of the discharge surface and the discharge ports, then the coloring agent contained in the ink mist is coagulated or deposited. If the coloring agent is coagulated or deposited as described above, any solid matter is formed in the vicinity of the discharge surface and the discharge ports. Therefore, it is feared that the discharge may be disturbed or disordered for the reaction liquid and the ink composition.
In view of the above, an object of an aspect of the present teaching is to provide an image forming apparatus which makes it possible to suppress the coagulation or the deposition of a coloring agent in the vicinity of a discharge port.